Geodetic instrument.



No- 76'1,4 s1. v I PATENTEDVMAY, 31, 1904.

- K; HEIN.

GEODETIG INSTRUMENT.

. 7 APPLICATION 'rILnn ma. '1, 190a. 10 1013111..

'///////////////// llllj INVENTOR ATTORNEYS THE nonms PETERS co. Pnoto u'rnou WASHINGTON, n. c.

UNITED STATES Patented. ma 31, 1904.

PATENT ()FFICE.

KARL HEIN, or HANOVER, GERMANY.

"GEODET IC INSTRUMENT.

SPECIFICATION forming part of Letters Patent No. 761,481, datedMay 31, 1904. I

. Application filed March 7, 1902.

To all whom, it may concern:

Be it known that I, KARL HEIN, a subject of the Emperor of Germany, residing in Hanover, Germany, have invented an Improved Geodetic Instrument, of which the following is a specification.

The invention relates to geodetic instruments, such as a theodolite, and has for its object to improve the mounting and centering of the various parts which are adapted for rotatable motion one with the other.

' In the accompanyingdrawings,'Figure 1 is.

it vertical cross-section of one form of theodoite. ing the supporting-pin in one piece, and Fig. 3 is a similar view showing a cardanic support for the theodolite.

On the conical supporting-pin a (which in Figs. 1 and 2 is shown connected with the plate 6 of a tripod or other stand provided with adjusting-screws) the limbs c, the alidade d, and the telescope-supporter e are set up one over the other. I l s H Though I have shown and described but the rudimentary elements of a theodolite in this application, it will be understood that one skilledin the art may supply or attach to the various supports shown any known form of Vernier, compass, nonius for the horizontalcircle limbus, or like elements.

In the instruments hitherto usedfor instance, in simple theodolites, the vertical alidade-axis, and in repetitiontheodolitesboth the vertical alidade axis and the vertical limbaxis were set into the vertical case of the" tripod, while onto the tripod-case or onto a hook under the same the plummet f was hung,

as in Fig. 1, by means of which thevertical axis of the instrument was to be exactly ce'n Fig. 2 is a vertical cross-section show- Serial No. 146,677. (No mbdel.)

as it also carries the instrumentsupports, which are fixed centrically and rotatably one over the other, points exactly to the nadir- The most exact centering can be effected with absolute certainty, even with an obliquelyplaced tripod, if the uninterrupted supportingpin' or supporting-rod, carried through down- "ward, moves in a joint after the manner of the cardanic suspension, Fig. 3.

The continuous supporting-pin or supporting-rod a may also consist of several pieces, which are put together before use. This is necessary if the apparatus must be used not only on a tripod but on a column.

I claim as my invention 1. A geodetic instrument, having a number of instrument-supports, one mounted above and free of theother on a common axis, and each independently rotatable on the common axis, substantially as described.

2. A geodetic instrument, having a number of instrument-supports, one mounted above and free of the other on a common axial pin, and each independently rotatable on the common axis, and a support for the axial pin, a continuation of the pin passing through and below said'pin-sup port, substantially as described.

3. A geodetic instrument, having a pin, a support therefor, alimb and an alidade, each mounted on the pin, one above and free of the other, and each adapted to revolve on said pin independently, substantially as described.

4. A geodetic instrument, having a conical pin, a support therefor, an alidade to'fit one portion of the conical pin, and rotatably mounted thereon, and a limb mounted on the pin, free of the alidade, substantially as described.

5". A geodetic instrument, having an upto the pin depending below the support for the plummet, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing Witnesses.

KARL l-IEIN.

Witnesses:

VICTOR HEIN, LEONORE Rnson. 

